This invention relates to a golf ball construction which, by virtue of certain carefully selected dimensions, is characterized by improved performance characteristics.
The United States Golf Association has set a variety of rules relative to the game of golf. These include rules governing the equipment that may be used in any golfing event purporting to follow the USGA restrictions.
With respect to golf balls, certain rules govern the ball diameter and weight. Specifically, an official USGA ball must have a diameter of at least 1.680 inches and it must not weigh more than 1.620 ounces. Other specifications govern initial velocity and distance when a golf ball is tested under certain controlled conditions.
With restrictions placed on size and weight, improvements in golf ball performance have focused on the use of new materials for making balls, and on dimple patterns designed to improve characteristics such as accuracy and longer carry. In the former regard, the introduction of two-piece balls consisting of a solid polymeric core and a resin cover material comprising, for example, a Surlyn material manufactured by E. I. du Pont, has constituted a major advance. Such balls have excellent cut resistance and, by utilizing different blends of resins, both distance and "feel" sought by golfers can be achieved.
Dimple patterns have been developed to enhance the flight characteristics of golf balls. In the 1970's, one pattern of choice was the so-called "Atti" design wherein the ball surface was divided into eight generally triangular areas. The resulting dimple pattern comprised 336 dimples which were approximately 0.135 inches in diameter.
By at least the early 1980's, the preference in dimple patterns shifted to an arrangement wherein the dimples are located within a plurality of pentagons, trapezoids, and triangles.
With such patterns, the numbers of dimples increased for example, to 384 or 492 dimples. Thus, without any significant change in dimple size, the surface area coverage by the dimples was increased to 75% or more and this enhanced the golf ball flight characteristics. Pocklington U.S. Pat. No. 4,932,664 is an example of this approach.
Attempts have also been made to use increased size as a basis for improving ball performance. New Zealand Patent No. 192,618 published in 1980 suggested use of ball diameters of 1.7 inches and greater. A Lynx "Jumbo" ball sold at about this same time had a diameter of about 1.8 inches. More recently, as described in U.S. Pat. No. 5,273,287, it is suggested that a ball varying in diameter between 1.7 and 1.8 inches will provide enhanced flight characteristics. It is stated that the ball should be of regulation weight, that is, no greater than 1.62 ounces, and that the increased diameter is achieved by using a core of standard diameter while increasing the cover thickness.
The balls described in U.S. Pat. No. 5,273,287 all include dimple patterns which cover at least 70% of the surface area. This ball, therefore, employs prior-developed icosahedron patterns or the like for improving flight characteristics, or new patterns achieving the same high density of dimples.